Issue with L5.4 (Validation)

[demogar]

When using a validation similar to this:

// ...
'picture' => 'image|max:1500',
//...

It gives an error like this one:

ErrorException: mb_strlen() expects parameter 1 to be string, object given

.../framework/src/Illuminate/Validation/Concerns/ValidatesAttributes.php:1344
.../framework/src/Illuminate/Validation/Concerns/ValidatesAttributes.php:895
.../framework/src/Illuminate/Validation/Validator.php:338
.../framework/src/Illuminate/Validation/Validator.php:253
.../framework/src/Illuminate/Validation/Validator.php:604

This is because, on ValidatesAttributes.php:1344 it expects a string, but it receives an ECodesleeve\Stapler\Attachment Object

Best regards.